论文标题
松弛动力学和长期尾巴解释了剪切引起的柔软altermal颗粒的扩散
Relaxation dynamics and long-time tails explain shear-induced diffusion of soft athermal particles near jamming
论文作者
论文摘要
我们在数值上研究了剪切诱导的二维软性颗粒的扩散。绿色kubo（GK）的关系适用于固定粒子附近颗粒的扩散系数，在该颗粒中，临界缩放率很好地解释了GK公式中的平均平方颗粒速度和放松时间。我们表明，如果系统低于干扰或剪切速率足够大，则横向速度的自动相关函数将拉伸指数。但是，如果系统高于干扰，并且剪切速率足够小，则自动相关表现出长期的尾巴，因此GK公式中的时间积分在两个维度上散开。我们提出了关键指数的经验缩放关系，并证明长期尾巴会对剪切诱导的扩散系数产生有限尺寸影响。
We numerically study shear-induced diffusion of soft athermal particles in two dimensions. The Green-Kubo (GK) relation is applicable to diffusion coefficient of the particles near jamming, where both mean squared particle velocities and relaxation time included in the GK formula are well explained by critical scaling. We show that auto-correlation functions of the transverse velocities are stretched exponential if the system is below jamming or shear rate is large enough. However, if the system is above jamming and the shear rate is sufficiently small, the auto-correlations exhibit long-time tails such that time integral in the GK formula diverges in two dimensions. We propose empirical scaling relations for the critical exponents and demonstrate that the long-time tails cause finite size effects on the shear-induced diffusion coefficient.
